NORTH Korea has been condemned by both China and Iran after the reclusive state issued a catalog of alarming threats against the South and the United States.

The unusually harsh rebukes of North Korea from China – Pyongyang's sole diplomatic and financial ally – came as Iran's foreign ministry urged against "provocative conduct" in the Korean peninsula.

China's message was one of exasperation after years of trying to coax North Korea out of isolation and to embrace economic reform.

No country "should be allowed to throw a region and even the whole world into chaos for selfish gain", President Xi Jinping told a forum on China's southern island of Hainan.

Although he did not name North Korea, President Xi Jinping appeared clearly to be referring to Pyongyang.

Foreign Minister Wang Yi added China opposed "provocative words and actions from any party in the region" and would not "allow trouble-making on China's doorstep".

Meanwhile, U.S. lawmakers have accused China of not doing enough to control the North.

Republican Senator John McCain, a member of the Senate Armed Services Committee, criticized China's "failure to rein in what could be a catastrophic situation".

China's actions, he said, "has been very disappointing. More than once, wars have started by accident and this is a very serious situation."

Analysts said that whatever influence China once had as North Korea's principal backer had waned.

"China has some say over its economic relations with the North but doesn't have the power to say 'don't do it' when it comes to nuclear weapons and political and military issues," said Kim Yeon-chul, professor of unification studies at South Korea's Inje University.

"North Korea is not listening to China."

Beijing negotiated the new U.N. sanctions following the February nuclear test and has said it wanted them implemented.

The measures tighten financial curbs on North Korea, order checks of suspicious cargo and strengthen a ban on luxury goods entering the country.

North Korea has said nuclear conflict could break out at any time on the Korean peninsula

North Korea is not listening to China

Kim Yeon-chul

Iran, meanwhile, blamed the North's apocalyptic threats of nuclear war on stability being compromised in the North by an American military build-up, reports have claimed.

"Our advice to all sides involved is to not stoke tensions by engaging in provocative conduct," ministry spokesman Ramin Mehmanparast said in remarks reported by the Mehr news agency.

"The climate should not remain one of threats," he said.

Mehmanparast accused arch-foe United States of provoking the crisis.

"The military build-up and provocative acts... by a country situated thousands of miles away is destabilising this region," he said referring to the United States.

He said, "the actions of all sides could spin out of control and damage the whole region."

Tensions in the peninsula have flared

Meanwhile, a top South Korean official has said he misspoke when he revealed there is an "indication" that North Korea is preparing for a nuclear test today.

Speculation had been building that North Korea could carry out a missile test as early as this week after dictator Kim Jong-un warned he could not "guarantee the safety of foreigners" after April 10.

Movement around an atomic test site in the North indicates the reclusive state may soon stage another nuclear test, South Korean official Ryoo Kihi-jae told a parliamentary committee.

He declined to give details on grounds that the matter was "intelligence related".

The movement of manpower and vehicles at the Punggye-ri test site is similar to that observed before the controverisal February blast – which initially sparked tensions following UN sanctions – reports have said.

Tensions have escalated further after North Korean authorities told embassies in Pyongyang they could not guarantee their safety from Wednesday - after saying conflict was inevitable amid joint U.S.-South Korean military exercises due to last until the end of the month.

However, no diplomats appear to have left the North Korean capital, despite a North Korean general reprotedly warning diplomats at the weekend that the situation remained "grave".

A North Korean military dog bites a portrait of South Korea's Defence Minister Kim Kwan-jin

William Hague yesterday urged world leaders to remain calm over growing threats from North Korea.

The Foreign Secretary admitted that hostility from the rogue state is something Britain “should be concerned about”. But dismissed fears that the country is on the brink of war.

“There’s a threat to the world from any country breaching the non-proliferation treaty, which North Korea is doing, acting in contravention of a whole series of UN Security Council resolutions and setting out to develop more and more longer range weapons, testing new nuclear weapons and indulging in the proliferation of many items to other countries as well," he said.

“We should be concerned about that. There is a danger in that. But it is important to stress we haven’t seen in recent days, in recent weeks, a change in what is happening in North Korean society.